blob: aa127ba392a45cbabe9f95180876543dd6441865 [file] [log] [blame]
/*
* Copyright (C) 2012-2013 MundoReader S.L.
* Author: Heiko Stuebner <heiko@sntech.de>
*
* based in parts on Nook zforce driver
*
* Copyright (C) 2010 Barnes & Noble, Inc.
* Author: Pieter Truter<ptruter@intrinsyc.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/hrtimer.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/input/mt.h>
#include <linux/platform_data/zforce_ts.h>
#define WAIT_TIMEOUT msecs_to_jiffies(1000)
#define FRAME_START 0xee
/* Offsets of the different parts of the payload the controller sends */
#define PAYLOAD_HEADER 0
#define PAYLOAD_LENGTH 1
#define PAYLOAD_BODY 2
/* Response offsets */
#define RESPONSE_ID 0
#define RESPONSE_DATA 1
/* Commands */
#define COMMAND_DEACTIVATE 0x00
#define COMMAND_INITIALIZE 0x01
#define COMMAND_RESOLUTION 0x02
#define COMMAND_SETCONFIG 0x03
#define COMMAND_DATAREQUEST 0x04
#define COMMAND_SCANFREQ 0x08
#define COMMAND_STATUS 0X1e
/*
* Responses the controller sends as a result of
* command requests
*/
#define RESPONSE_DEACTIVATE 0x00
#define RESPONSE_INITIALIZE 0x01
#define RESPONSE_RESOLUTION 0x02
#define RESPONSE_SETCONFIG 0x03
#define RESPONSE_SCANFREQ 0x08
#define RESPONSE_STATUS 0X1e
/*
* Notifications are send by the touch controller without
* being requested by the driver and include for example
* touch indications
*/
#define NOTIFICATION_TOUCH 0x04
#define NOTIFICATION_BOOTCOMPLETE 0x07
#define NOTIFICATION_OVERRUN 0x25
#define NOTIFICATION_PROXIMITY 0x26
#define NOTIFICATION_INVALID_COMMAND 0xfe
#define ZFORCE_REPORT_POINTS 2
#define ZFORCE_MAX_AREA 0xff
#define STATE_DOWN 0
#define STATE_MOVE 1
#define STATE_UP 2
#define SETCONFIG_DUALTOUCH (1 << 0)
struct zforce_point {
int coord_x;
int coord_y;
int state;
int id;
int area_major;
int area_minor;
int orientation;
int pressure;
int prblty;
};
/*
* @client the i2c_client
* @input the input device
* @suspending in the process of going to suspend (don't emit wakeup
* events for commands executed to suspend the device)
* @suspended device suspended
* @access_mutex serialize i2c-access, to keep multipart reads together
* @command_done completion to wait for the command result
* @command_mutex serialize commands send to the ic
* @command_waiting the id of the command that that is currently waiting
* for a result
* @command_result returned result of the command
*/
struct zforce_ts {
struct i2c_client *client;
struct input_dev *input;
const struct zforce_ts_platdata *pdata;
char phys[32];
bool suspending;
bool suspended;
bool boot_complete;
/* Firmware version information */
u16 version_major;
u16 version_minor;
u16 version_build;
u16 version_rev;
struct mutex access_mutex;
struct completion command_done;
struct mutex command_mutex;
int command_waiting;
int command_result;
};
static int zforce_command(struct zforce_ts *ts, u8 cmd)
{
struct i2c_client *client = ts->client;
char buf[3];
int ret;
dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
buf[0] = FRAME_START;
buf[1] = 1; /* data size, command only */
buf[2] = cmd;
mutex_lock(&ts->access_mutex);
ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
mutex_unlock(&ts->access_mutex);
if (ret < 0) {
dev_err(&client->dev, "i2c send data request error: %d\n", ret);
return ret;
}
return 0;
}
static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
{
struct i2c_client *client = ts->client;
int ret;
ret = mutex_trylock(&ts->command_mutex);
if (!ret) {
dev_err(&client->dev, "already waiting for a command\n");
return -EBUSY;
}
dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
buf[1], buf[2]);
ts->command_waiting = buf[2];
mutex_lock(&ts->access_mutex);
ret = i2c_master_send(client, buf, len);
mutex_unlock(&ts->access_mutex);
if (ret < 0) {
dev_err(&client->dev, "i2c send data request error: %d\n", ret);
goto unlock;
}
dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
ret = -ETIME;
goto unlock;
}
ret = ts->command_result;
unlock:
mutex_unlock(&ts->command_mutex);
return ret;
}
static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
{
struct i2c_client *client = ts->client;
char buf[3];
int ret;
dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
buf[0] = FRAME_START;
buf[1] = 1; /* data size, command only */
buf[2] = cmd;
ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
if (ret < 0) {
dev_err(&client->dev, "i2c send data request error: %d\n", ret);
return ret;
}
return 0;
}
static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
{
struct i2c_client *client = ts->client;
char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
(x & 0xff), ((x >> 8) & 0xff),
(y & 0xff), ((y >> 8) & 0xff) };
dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
}
static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
u16 stylus)
{
struct i2c_client *client = ts->client;
char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
(idle & 0xff), ((idle >> 8) & 0xff),
(finger & 0xff), ((finger >> 8) & 0xff),
(stylus & 0xff), ((stylus >> 8) & 0xff) };
dev_dbg(&client->dev, "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
idle, finger, stylus);
return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
}
static int zforce_setconfig(struct zforce_ts *ts, char b1)
{
struct i2c_client *client = ts->client;
char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
b1, 0, 0, 0 };
dev_dbg(&client->dev, "set config to (%d)\n", b1);
return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
}
static int zforce_start(struct zforce_ts *ts)
{
struct i2c_client *client = ts->client;
const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
int ret;
dev_dbg(&client->dev, "starting device\n");
ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
if (ret) {
dev_err(&client->dev, "Unable to initialize, %d\n", ret);
return ret;
}
ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
if (ret) {
dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
goto error;
}
ret = zforce_scan_frequency(ts, 10, 50, 50);
if (ret) {
dev_err(&client->dev, "Unable to set scan frequency, %d\n",
ret);
goto error;
}
if (zforce_setconfig(ts, SETCONFIG_DUALTOUCH)) {
dev_err(&client->dev, "Unable to set config\n");
goto error;
}
/* start sending touch events */
ret = zforce_command(ts, COMMAND_DATAREQUEST);
if (ret) {
dev_err(&client->dev, "Unable to request data\n");
goto error;
}
/*
* Per NN, initial cal. take max. of 200msec.
* Allow time to complete this calibration
*/
msleep(200);
return 0;
error:
zforce_command_wait(ts, COMMAND_DEACTIVATE);
return ret;
}
static int zforce_stop(struct zforce_ts *ts)
{
struct i2c_client *client = ts->client;
int ret;
dev_dbg(&client->dev, "stopping device\n");
/* Deactivates touch sensing and puts the device into sleep. */
ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
if (ret != 0) {
dev_err(&client->dev, "could not deactivate device, %d\n",
ret);
return ret;
}
return 0;
}
static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
{
struct i2c_client *client = ts->client;
const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
struct zforce_point point;
int count, i, num = 0;
count = payload[0];
if (count > ZFORCE_REPORT_POINTS) {
dev_warn(&client->dev, "to many coordinates %d, expected max %d\n",
count, ZFORCE_REPORT_POINTS);
count = ZFORCE_REPORT_POINTS;
}
for (i = 0; i < count; i++) {
point.coord_x =
payload[9 * i + 2] << 8 | payload[9 * i + 1];
point.coord_y =
payload[9 * i + 4] << 8 | payload[9 * i + 3];
if (point.coord_x > pdata->x_max ||
point.coord_y > pdata->y_max) {
dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
point.coord_x, point.coord_y);
point.coord_x = point.coord_y = 0;
}
point.state = payload[9 * i + 5] & 0x03;
point.id = (payload[9 * i + 5] & 0xfc) >> 2;
/* determine touch major, minor and orientation */
point.area_major = max(payload[9 * i + 6],
payload[9 * i + 7]);
point.area_minor = min(payload[9 * i + 6],
payload[9 * i + 7]);
point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
point.pressure = payload[9 * i + 8];
point.prblty = payload[9 * i + 9];
dev_dbg(&client->dev,
"point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
i, count, point.state, point.id,
point.pressure, point.prblty,
point.coord_x, point.coord_y,
point.area_major, point.area_minor,
point.orientation);
/* the zforce id starts with "1", so needs to be decreased */
input_mt_slot(ts->input, point.id - 1);
input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
point.state != STATE_UP);
if (point.state != STATE_UP) {
input_report_abs(ts->input, ABS_MT_POSITION_X,
point.coord_x);
input_report_abs(ts->input, ABS_MT_POSITION_Y,
point.coord_y);
input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
point.area_major);
input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
point.area_minor);
input_report_abs(ts->input, ABS_MT_ORIENTATION,
point.orientation);
num++;
}
}
input_mt_sync_frame(ts->input);
input_mt_report_finger_count(ts->input, num);
input_sync(ts->input);
return 0;
}
static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
{
struct i2c_client *client = ts->client;
int ret;
mutex_lock(&ts->access_mutex);
/* read 2 byte message header */
ret = i2c_master_recv(client, buf, 2);
if (ret < 0) {
dev_err(&client->dev, "error reading header: %d\n", ret);
goto unlock;
}
if (buf[PAYLOAD_HEADER] != FRAME_START) {
dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
ret = -EIO;
goto unlock;
}
if (buf[PAYLOAD_LENGTH] <= 0 || buf[PAYLOAD_LENGTH] > 255) {
dev_err(&client->dev, "invalid payload length: %d\n",
buf[PAYLOAD_LENGTH]);
ret = -EIO;
goto unlock;
}
/* read the message */
ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
if (ret < 0) {
dev_err(&client->dev, "error reading payload: %d\n", ret);
goto unlock;
}
dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
unlock:
mutex_unlock(&ts->access_mutex);
return ret;
}
static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
{
struct i2c_client *client = ts->client;
if (ts->command_waiting == cmd) {
dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
ts->command_result = result;
complete(&ts->command_done);
} else {
dev_dbg(&client->dev, "command %d not for us\n", cmd);
}
}
static irqreturn_t zforce_irq(int irq, void *dev_id)
{
struct zforce_ts *ts = dev_id;
struct i2c_client *client = ts->client;
if (ts->suspended && device_may_wakeup(&client->dev))
pm_wakeup_event(&client->dev, 500);
return IRQ_WAKE_THREAD;
}
static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
{
struct zforce_ts *ts = dev_id;
struct i2c_client *client = ts->client;
const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
int ret;
u8 payload_buffer[512];
u8 *payload;
/*
* When still suspended, return.
* Due to the level-interrupt we will get re-triggered later.
*/
if (ts->suspended) {
msleep(20);
return IRQ_HANDLED;
}
dev_dbg(&client->dev, "handling interrupt\n");
/* Don't emit wakeup events from commands run by zforce_suspend */
if (!ts->suspending && device_may_wakeup(&client->dev))
pm_stay_awake(&client->dev);
while (!gpio_get_value(pdata->gpio_int)) {
ret = zforce_read_packet(ts, payload_buffer);
if (ret < 0) {
dev_err(&client->dev, "could not read packet, ret: %d\n",
ret);
break;
}
payload = &payload_buffer[PAYLOAD_BODY];
switch (payload[RESPONSE_ID]) {
case NOTIFICATION_TOUCH:
/*
* Always report touch-events received while
* suspending, when being a wakeup source
*/
if (ts->suspending && device_may_wakeup(&client->dev))
pm_wakeup_event(&client->dev, 500);
zforce_touch_event(ts, &payload[RESPONSE_DATA]);
break;
case NOTIFICATION_BOOTCOMPLETE:
ts->boot_complete = payload[RESPONSE_DATA];
zforce_complete(ts, payload[RESPONSE_ID], 0);
break;
case RESPONSE_INITIALIZE:
case RESPONSE_DEACTIVATE:
case RESPONSE_SETCONFIG:
case RESPONSE_RESOLUTION:
case RESPONSE_SCANFREQ:
zforce_complete(ts, payload[RESPONSE_ID],
payload[RESPONSE_DATA]);
break;
case RESPONSE_STATUS:
/*
* Version Payload Results
* [2:major] [2:minor] [2:build] [2:rev]
*/
ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
payload[RESPONSE_DATA];
ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
payload[RESPONSE_DATA + 2];
ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
payload[RESPONSE_DATA + 4];
ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
payload[RESPONSE_DATA + 6];
dev_dbg(&ts->client->dev, "Firmware Version %04x:%04x %04x:%04x\n",
ts->version_major, ts->version_minor,
ts->version_build, ts->version_rev);
zforce_complete(ts, payload[RESPONSE_ID], 0);
break;
case NOTIFICATION_INVALID_COMMAND:
dev_err(&ts->client->dev, "invalid command: 0x%x\n",
payload[RESPONSE_DATA]);
break;
default:
dev_err(&ts->client->dev, "unrecognized response id: 0x%x\n",
payload[RESPONSE_ID]);
break;
}
}
if (!ts->suspending && device_may_wakeup(&client->dev))
pm_relax(&client->dev);
dev_dbg(&client->dev, "finished interrupt\n");
return IRQ_HANDLED;
}
static int zforce_input_open(struct input_dev *dev)
{
struct zforce_ts *ts = input_get_drvdata(dev);
int ret;
ret = zforce_start(ts);
if (ret)
return ret;
return 0;
}
static void zforce_input_close(struct input_dev *dev)
{
struct zforce_ts *ts = input_get_drvdata(dev);
struct i2c_client *client = ts->client;
int ret;
ret = zforce_stop(ts);
if (ret)
dev_warn(&client->dev, "stopping zforce failed\n");
return;
}
#ifdef CONFIG_PM_SLEEP
static int zforce_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct zforce_ts *ts = i2c_get_clientdata(client);
struct input_dev *input = ts->input;
int ret = 0;
mutex_lock(&input->mutex);
ts->suspending = true;
/*
* When configured as a wakeup source device should always wake
* the system, therefore start device if necessary.
*/
if (device_may_wakeup(&client->dev)) {
dev_dbg(&client->dev, "suspend while being a wakeup source\n");
/* Need to start device, if not open, to be a wakeup source. */
if (!input->users) {
ret = zforce_start(ts);
if (ret)
goto unlock;
}
enable_irq_wake(client->irq);
} else if (input->users) {
dev_dbg(&client->dev, "suspend without being a wakeup source\n");
ret = zforce_stop(ts);
if (ret)
goto unlock;
disable_irq(client->irq);
}
ts->suspended = true;
unlock:
ts->suspending = false;
mutex_unlock(&input->mutex);
return ret;
}
static int zforce_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct zforce_ts *ts = i2c_get_clientdata(client);
struct input_dev *input = ts->input;
int ret = 0;
mutex_lock(&input->mutex);
ts->suspended = false;
if (device_may_wakeup(&client->dev)) {
dev_dbg(&client->dev, "resume from being a wakeup source\n");
disable_irq_wake(client->irq);
/* need to stop device if it was not open on suspend */
if (!input->users) {
ret = zforce_stop(ts);
if (ret)
goto unlock;
}
} else if (input->users) {
dev_dbg(&client->dev, "resume without being a wakeup source\n");
enable_irq(client->irq);
ret = zforce_start(ts);
if (ret < 0)
goto unlock;
}
unlock:
mutex_unlock(&input->mutex);
return ret;
}
#endif
static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
static void zforce_reset(void *data)
{
struct zforce_ts *ts = data;
gpio_set_value(ts->pdata->gpio_rst, 0);
}
static int zforce_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
struct zforce_ts *ts;
struct input_dev *input_dev;
int ret;
if (!pdata)
return -EINVAL;
ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
ret = devm_gpio_request_one(&client->dev, pdata->gpio_int, GPIOF_IN,
"zforce_ts_int");
if (ret) {
dev_err(&client->dev, "request of gpio %d failed, %d\n",
pdata->gpio_int, ret);
return ret;
}
ret = devm_gpio_request_one(&client->dev, pdata->gpio_rst,
GPIOF_OUT_INIT_LOW, "zforce_ts_rst");
if (ret) {
dev_err(&client->dev, "request of gpio %d failed, %d\n",
pdata->gpio_rst, ret);
return ret;
}
ret = devm_add_action(&client->dev, zforce_reset, ts);
if (ret) {
dev_err(&client->dev, "failed to register reset action, %d\n",
ret);
return ret;
}
snprintf(ts->phys, sizeof(ts->phys),
"%s/input0", dev_name(&client->dev));
input_dev = devm_input_allocate_device(&client->dev);
if (!input_dev) {
dev_err(&client->dev, "could not allocate input device\n");
return -ENOMEM;
}
mutex_init(&ts->access_mutex);
mutex_init(&ts->command_mutex);
ts->pdata = pdata;
ts->client = client;
ts->input = input_dev;
input_dev->name = "Neonode zForce touchscreen";
input_dev->phys = ts->phys;
input_dev->id.bustype = BUS_I2C;
input_dev->open = zforce_input_open;
input_dev->close = zforce_input_close;
__set_bit(EV_KEY, input_dev->evbit);
__set_bit(EV_SYN, input_dev->evbit);
__set_bit(EV_ABS, input_dev->evbit);
/* For multi touch */
input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
pdata->x_max, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
pdata->y_max, 0, 0);
input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
ZFORCE_MAX_AREA, 0, 0);
input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
ZFORCE_MAX_AREA, 0, 0);
input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
input_set_drvdata(ts->input, ts);
init_completion(&ts->command_done);
/*
* The zforce pulls the interrupt low when it has data ready.
* After it is triggered the isr thread runs until all the available
* packets have been read and the interrupt is high again.
* Therefore we can trigger the interrupt anytime it is low and do
* not need to limit it to the interrupt edge.
*/
ret = devm_request_threaded_irq(&client->dev, client->irq,
zforce_irq, zforce_irq_thread,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
input_dev->name, ts);
if (ret) {
dev_err(&client->dev, "irq %d request failed\n", client->irq);
return ret;
}
i2c_set_clientdata(client, ts);
/* let the controller boot */
gpio_set_value(pdata->gpio_rst, 1);
ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
dev_warn(&client->dev, "bootcomplete timed out\n");
/* need to start device to get version information */
ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
if (ret) {
dev_err(&client->dev, "unable to initialize, %d\n", ret);
return ret;
}
/* this gets the firmware version among other informations */
ret = zforce_command_wait(ts, COMMAND_STATUS);
if (ret < 0) {
dev_err(&client->dev, "couldn't get status, %d\n", ret);
zforce_stop(ts);
return ret;
}
/* stop device and put it into sleep until it is opened */
ret = zforce_stop(ts);
if (ret < 0)
return ret;
device_set_wakeup_capable(&client->dev, true);
ret = input_register_device(input_dev);
if (ret) {
dev_err(&client->dev, "could not register input device, %d\n",
ret);
return ret;
}
return 0;
}
static struct i2c_device_id zforce_idtable[] = {
{ "zforce-ts", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, zforce_idtable);
static struct i2c_driver zforce_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "zforce-ts",
.pm = &zforce_pm_ops,
},
.probe = zforce_probe,
.id_table = zforce_idtable,
};
module_i2c_driver(zforce_driver);
MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
MODULE_DESCRIPTION("zForce TouchScreen Driver");
MODULE_LICENSE("GPL");